1. Field of the Invention
This invention generally relates to user interface/device controllers for radio receivers and more specifically to radio receiver controllers that perform authentication with the controlled radio receiver.
2. Description of Related Art
Radio receivers are sometimes designed to support separate controllers, often referred to as control heads, that allow a user to enter control commands for the receiver. These separate controllers also often display data produced by or related to the radio, such as the currently tuned channel information, volume setting, received signal strength, and other radio operating information. Control heads are also able to display other data produced by a receiver that it is controlling, such as programming metadata received by the receiver. One example of such programming metadata is provided by subscription satellite radio services, such as Satellite Digital Audio Radio Service (SDARS) that include systems operated by Sirius Satellite Radio, Incorporated and XM Satellite Radio Holdings, Incorporated. These subscription satellite radio services broadcast metadata that includes the song title and song artist for a song currently being played on the currently tuned channel of the subscription radio receiver. The use of separate controllers enhances the flexibility in mounting for the radio receiver and the separate controller. An example of one advantage is for installations of radio receivers in a motor vehicle. In a motor vehicle installation, the separate controller has a much smaller size than the entire radio receiver and can be mounted more conveniently and in a manner that consumes much less space. The radio receiver in such an installation can be mounted anywhere in the vehicle that can accommodate its space and power requirements. A further example of the advantageous use of separate controllers is the use of wireless controllers that allow users to freely pass around and use the wireless controller anywhere within wireless range of the radio receiver.
Manufacturers of radio receivers also produce the separate controllers that are used to control those radios. The radio receiver and the separate controller generally communicate over a wired or wireless data link that allows the exchange of control commands for the radio receiver and data provided by the radio receiver that is to be displayed on the separate controller. The use of a conventional data link for the connection between the radio receiver and the separate controller allows a third party to determine the characteristics of that connection and manufacture substitute separate controllers. The presence of unauthorized third party separate controllers may facilitate unauthorized duplication of copyrighted radio content and further deprives the manufacturer of the radio receiver of control over the appearance presented to a user of the radio receiver, and therefore limits the enthusiasm of manufacturers to support and provide separate controllers for their radio receivers and deprives the public of their benefits. Incorporating conventional data security processes in the radio receiver and the separate controller would unduly add to the complexity of these devices.
Therefore a need exists to overcome the problems with the prior art as discussed above.